| 摘要 |
PURPOSE:To ensure a correct quantitative detection of high spots without any high spot detection failure or excessive detection, by providing a method which makes use of an approximate curve obtained from a combined measured value which in turn is calculated through substitution of a part of the measured values by a corrected measured values attained on an assumption that there is no high spot. CONSTITUTION:Positions XA, XB and thickness deviations DELTAHA', DELTAHA of high spots A', A are automatically detected through minimizing the influences of abnormal part B and excessive high spot A. An approximate curve approximating the thickness profile is obtained through a partial approximating method such as a moving adding mean method, from the measured values of thickness obtained by means of a thickness measuring device 2. Curves Yu and Yi are drawn by adding and subtracting, respectively, allowances deltau and deltai to and from this primary reference curve Y(i). The part of the thickness profile having no high spot nor abnormality in the measurement is involved by the area between the curves Yu and Yi. However, the thickness profile part having a large high spot or abnormality in the measurement comes out of this area. |
